Russian author in conversation with Mark (5,3)

I believe the answer is:

check off

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'mark' is the definition.
(synonyms)

I don't understand the remainder of the clue.

(Other definitions for check off that I've seen before include "Tick names on list" , "Maybe put a tick against" , "mark listed items systematically" , "Record correct" .)

I've seen this clue in The Hindu.

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